FDA survey of retail meat identifies Salmonella with antibiotic resistance genes not seen before in the US

The Center for Veterinary Medicine at the FDA have published a report on antimicrobial resistance in Salmonella found in raw meat. While multi-drug resistance has dropped substantially since 2011, two genes conferring resistance to the medically important antibiotics ciprofloxacin and ceftriaxone were found in single pork and chicken samples. These specific resistance genes had not been detected in the US before. The report was the first to use whole genome sequencing data, enabling identification and tracking of the genes causing antimicrobial resistance.

 

Dr. Adina Howe, Assistant Professor, Agricultural and Biosystems Engineering, Iowa State University (webpage):

Expertise: Identifying microbial drivers of global change; biological indicators of environmental health; interactions within complex microbial communities.

“This report is not the first in the US of ciprafloxacin or ceftriaxone resistance, but rather the presence of a gene that may confer resistance to a specific antibiotic originating from a very specific environment.  It is important to recognize that the presence of a specific gene demonstrates the potential for resistance but does not demonstrate functional resistance or susceptibility to an antibiotic.

“While a single isolate is not enough evidence to suggest widespread antibiotic resistance, it is concerning that the Salmonella ciprofloxacin-resistant gene, like many other resistance genes, was found on a plasmid.  The location of resistance genes on plasmids is of great concern as this is a mechanism that allows genes to move between bacteria and spread.  Research efforts, like this one, that Identify these genes and the mechanisms for how they spread in the environment are very important to understanding how they impact our health and managing our current arsenal of antibiotics against these disease-causing bacteria.

“Whole genome sequencing is an exciting and affordable new technology that has changed the resolution that we can characterize microbes in the environment.  Combined with many other technologies, including microscopy and cell sorting techniques, sequencing helps us to understand complex microbial communities in our environment.  In particular, whole genome sequencing allows us to very specifically identify strains of interest and their genes.  The ability to resolve the locations of genes in relationship to one other is a powerful benefit to sequencing strategies.   Our biological toolbox to understand diverse environments, containing trillions of species, is growing and helping us to shed light on the role of AMR in agriculture.”

 

Declared interests (see GENeS register of interests policy):

No further interests declared.

Reference:

FDA Release: http://www.fda.gov/AnimalVeterinary/NewsEvents/CVMUpdates/ucm498038.htm?source=govdelivery&utm_medium=email&utm_source=govdelivery

Please feel free to leave your comments below, but be aware that by doing so you agree to our Terms & Conditions.